Movieclip as a button question

I have a movieclip working as a button on my stage, and I want it to trigger a nother movieclip from the library to load and play on release, in another location.
I’ve tried to make an empty movieclip to attach the new movieclip to, no luck, I’ve tried to just attachMovie and put the x y coordinates and thats nt working either.
The code I already have is

this.btn_4.onRelease= function(){ ("st_close"); ("st_close");

this part ("st_close"); ("st_close");

is making another movieclip do something, and it’s workig fine, but I can’tfigure out how to get the other movieclip to play on the screen. When I drag it on and use


it shows up behind the some of the other stuff, automatically plays. Even when I put


Hopefully I’m making sense- I know It’s probably a dumb question but I’m still learning, and my books are confusing me even more!
Thanks for helping:)